The field of the invention is in the data collection art and more particularly the art of automatically expressing a graphic curve in digital x-y coordinate form.
Many times, it is desirable to digitize y versus x data from plotted curves. Manually, it is a most tedious task with the probability of human errors occurring in reading data points from the plotted curves being great. Examples of the prior art devices to remove the human element from the conversion process are disclosed by the following U.S. patents; No. 3,803,588 to patentee LeSchack; No. 3,848,089 to patentee Stewart; No. 3,982,165 to patentee Rich; and No. 4,018,989 to patentees Snyder et al.